SEARCH FOR LUMINANCE CONTRAST THRESHOLDS FOR PAVEMENT MARKINGS

This study, performed in the field with observers traveling under normal day and night traffic conditions, is based on measurements of the retroflected luminance coefficient and of the luminance contrast made by the ECODYN high-speed measuring system. Comparing the observers' responses to the measurement results yields some useful items of information. Some concern quality criteria already covered by specifications, such as RL, and serve as a check of validity of the values currently applied. Others concern new quality criteria accessible with apparatus like ECODYN, such as CN and CJ, for which the values that best serve road users are still to be determined. The validity of the values of RL, corresponding to the French requirement with the geometry e = 3.5 degrees and a = 4.5 degrees and to the European requirement with e = 1.24 degrees and a = 2.29 degrees, is confirmed. Above a certain day contrast threshold, measured under an overcast sky or under a sunny sky, the great majority of the observers regard the markings as sufficiently visible.

Language

  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 255-274
  • Serial:
    • VTI Conferens
    • Publisher: Swedish National Road and Transport Research Institute (VTI)
    • ISSN: 0347-6049

Subject/Index Terms

Filing Info

  • Accession Number: 00723359
  • Record Type: Publication
  • Report/Paper Numbers: No. 4A, Part 5
  • Files: TRIS
  • Created Date: Jul 30 1996 12:00AM